OEM quality 7" tablet with steering wheel controls and backup camera

03-05-2012, 07:34 PM

I've lurked the forum for years and have recently been experimenting with installing my tablet into the dash of my car. I decided it was time to post what I have learned along the way and things I learn in the future along the way.

The tablet that I have decided to use on this build is a Dell Streak 7". I like things to look and function like OEM and I have run into several hurdles along the way, so I'll list what I have planned and what I learn on my build below here.

Front End - I will be using Android 4.0 with Cornerstone on this install. There is already a working beta for this device over on XDA forums, once the bugs are worked out I will upgrade my tablet. The final build of 4.0 for the DS7 is said to support Cornerstone which will be perfect for switching between media/nav/OBD in an incar installation. More info on Cornerstone can be found here: http://www.onskreen.com/cornerstone/

Internet Connectivity - OEM functionality means that the device should be connected to the internet without the use of my cell phone. My solution for this is to use a Cradlepoint MBR1000 (http://www.cradlepoint.com/products/mbr1000) router with a Verizon USB hotspot. This router will handle any authentication needed so it's a simple power on, power off, and can be hidden away in the car. As a bonus it gives me the opportunity to attach other devices to the local network in this project.

Steering Wheel Controls - This one was a must for me and the solution is very basic. I will be using an Arduino Dueliminove with ethernet shield to handle inputs from the steering wheel controls and will transmit that information to the tablet through something I call DQVE (Dock, HTTP Query, Set Variable, Execute Command). The concept here is very basic. The Arduino gets a command from the steering wheel controls and sets a variable, then it calls the DQVE process.

The DQVE process trips a USB pin so that the tablet thinks it has been docked

Tasker intercepts the dock and performs an HTTP query to the IP address of the Arduino

The HTTP query returns an XML file that is parsed and the variable is set

Tasker performs the associated command

I will map mute, vol+/vol-, and track+/ track- to the specified commands and mode will launch Vlingo for voice command.

Backup Camera - Having a router in the car will allow me to install IP cameras and I can use the DQVE process to trigger tasker to launch an IPCam viewer application when the reverse lights are on.

Power Management - The plan is for the tablet to always be powered on. It's default resting state will have all connections and display off. The DQVE process will tell the tablet to wake up once the Arduino boots with key on. Loss of WiFi signal from the router for more than 30 seconds will cause the tablet to go back into hibernation, also triggered by Tasker. 12v power will be pulled from the BCM of my vehicle which stays on after the vehicle has been shut off for X amount of time, so that the tablet can recharge if needed.

Dimmer - This will function the same as the backup camera. When the Arduino sees that the dash lights are on or off it will set the variable and trigger the DQVE process so that tasker can update the screen brightness.

Amplification - Because the headphone out only supports two channels (left/right) I will end up mirroring the front and rear channels. I'm not overly concerned about this because I don't watch movies or listen to many things with surround sound. The tablet does not have enough juice to drive the factory speakers so a 4x50 RMS amp will be installed behind the tablet where the factory headunit used to sit.

I think those are all the key points I can think of right now, everything else is basically what app to use for what. Once the stable build of Android 4.0 is released on XDA this project can officially take flight. I'll update this with my thoughts and ramblings as they develop.

Well thought out plan, I have subscribed and will be keeping a close watch on your build. I agree that if you are going to install something like this then full integration is the only way to go. I am currently in planning stage and your DQVE process sounds really easy when it is broken down as such.BTW have you thought about the lack of FM tuner and DVD/ Cd drive? I'm not sure if this is a deal breaker for me. As far as the back up camera, you may now have an alternative to an IP cam with the release of 4.0 ICS. I posted on a different thread here and also at XDA a really interesting site I found today. A guy in HK has been able to integrate a usb cam w/ 4.0 This would still give you camera access without needing an internet signal. http://brain.cc.kogakuin.ac.jp/research/usb-e.html

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Well thought out plan, I have subscribed and will be keeping a close watch on your build. I agree that if you are going to install something like this then full integration is the only way to go. I am currently in planning stage and your DQVE process sounds really easy when it is broken down as such.BTW have you thought about the lack of FM tuner and DVD/ Cd drive? I'm not sure if this is a deal breaker for me. As far as the back up camera, you may now have an alternative to an IP cam with the release of 4.0 ICS. I posted on a different thread here and also at XDA a really interesting site I found today. A guy in HK has been able to integrate a usb cam w/ 4.0 This would still give you camera access without needing an internet signal. http://brain.cc.kogakuin.ac.jp/research/usb-e.html

Thanks.

The lack of FM tuner I have considered and I will be using an app called TuneIn radio, it streams all the local stations that I listen to over the air.

The lack of CD/DVD drive bothered me at first, but I realized that I don't have many CDs anymore, everything is digital and I have no interest in DVD's while driving so this wont bother me to much.

I saw that post but I'm not sure that the tablet I am using has the required hardware since it is not a native 4.0 ICS tablet. The IP camera will work anytime the router is on (even without internet access) so no reason to worry there. If I can do everything I want without cracking the tablet open that is even better.

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I would assume he just meant the size of icons and such. I'm currently using a 7" Acer Iconia A100 in my civic's dash and it's not bad, but bigger icons would be more convenient. There are a few "car home" apps, but I've never been happy with the aesthetics AND functionality combined. However, I don't use that many different apps so it's not too big a deal so far.

For power you can also just use Tasker to trigger all your screen and wireless settings. Mine is spliced into the cig lighter so when the ignition is on/off Tasker turns specific settings on/off. I've found that the tablet will last almost a week without charging.

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Awesome plan! Was hoping to see more and more tablet type development! Saving up for a tablet install myself (galaxy tab 7.7").

Was particularly interested in how you are doing the steering wheel controls.... definitely going to keep an eye on this thread.

I was thinking of using a programmable usb keyboard controller (like an I-PAC, used for MAME arcade controls) for my steering buttons interfacing to android in usb host mode with a usb-to-go cable...

I came upon this page http://norvangorgi.blogspot.com/2011...mote-with.html that describes how to re-map bluetooth hid profiles, should work with usb hid devices as well...waiting for my usb host mode cable to come in before I start testing on my Galaxy Note....might be an other simpler option?

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Awesome plan! Was hoping to see more and more tablet type development! Saving up for a tablet install myself (galaxy tab 7.7").

Was particularly interested in how you are doing the steering wheel controls.... definitely going to keep an eye on this thread.

I was thinking of using a programmable usb keyboard controller (like an I-PAC, used for MAME arcade controls) for my steering buttons interfacing to android in usb host mode with a usb-to-go cable...

I came upon this page http://norvangorgi.blogspot.com/2011...mote-with.html that describes how to re-map bluetooth hid profiles, should work with usb hid devices as well...waiting for my usb host mode cable to come in before I start testing on my Galaxy Note....might be an other simpler option?

Best of luck and regards,

That's a cool idea however I am using bluetooth for an OBDII scanner.

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I would assume he just meant the size of icons and such. I'm currently using a 7" Acer Iconia A100 in my civic's dash and it's not bad, but bigger icons would be more convenient. There are a few "car home" apps, but I've never been happy with the aesthetics AND functionality combined. However, I don't use that many different apps so it's not too big a deal so far.

For power you can also just use Tasker to trigger all your screen and wireless settings. Mine is spliced into the cig lighter so when the ignition is on/off Tasker turns specific settings on/off. I've found that the tablet will last almost a week without charging.http://www.mp3car.com/members/btbond.htmlHere's my install if you're curious.

You've got some great ideas. I'm curious to see the steering wheel controls in action. Good luck with the install!

The size of the icons and screen can be changed by changing the resolution, or screen density. Also there are a few launchers that allow you to resize the icons and choose how many rows/columns of icons there are.

Tasker is handling my screen and wiring settings however the Tegra2 is a power hog and I can only get a day or two in standby, so I need to have the tablet charge after use to keep it above 90%.

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I've lurked the forum for years and have recently been experimenting with installing my tablet into the dash of my car. I decided it was time to post what I have learned along the way and things I learn in the future along the way.

The tablet that I have decided to use on this build is a Dell Streak 7". I like things to look and function like OEM and I have run into several hurdles along the way, so I'll list what I have planned and what I learn on my build below here.

Front End - I will be using Android 4.0 with Cornerstone on this install. There is already a working beta for this device over on XDA forums, once the bugs are worked out I will upgrade my tablet. The final build of 4.0 for the DS7 is said to support Cornerstone which will be perfect for switching between media/nav/OBD in an incar installation. More info on Cornerstone can be found here: http://www.onskreen.com/cornerstone/

Internet Connectivity - OEM functionality means that the device should be connected to the internet without the use of my cell phone. My solution for this is to use a Cradlepoint MBR1000 (http://www.cradlepoint.com/products/mbr1000) router with a Verizon USB hotspot. This router will handle any authentication needed so it's a simple power on, power off, and can be hidden away in the car. As a bonus it gives me the opportunity to attach other devices to the local network in this project.

Steering Wheel Controls - This one was a must for me and the solution is very basic. I will be using an Arduino Dueliminove with ethernet shield to handle inputs from the steering wheel controls and will transmit that information to the tablet through something I call DQVE (Dock, HTTP Query, Set Variable, Execute Command). The concept here is very basic. The Arduino gets a command from the steering wheel controls and sets a variable, then it calls the DQVE process.

The DQVE process trips a USB pin so that the tablet thinks it has been docked

Tasker intercepts the dock and performs an HTTP query to the IP address of the Arduino

The HTTP query returns an XML file that is parsed and the variable is set

Tasker performs the associated command

I will map mute, vol+/vol-, and track+/ track- to the specified commands and mode will launch Vlingo for voice command.

Backup Camera - Having a router in the car will allow me to install IP cameras and I can use the DQVE process to trigger tasker to launch an IPCam viewer application when the reverse lights are on.

Power Management - The plan is for the tablet to always be powered on. It's default resting state will have all connections and display off. The DQVE process will tell the tablet to wake up once the Arduino boots with key on. Loss of WiFi signal from the router for more than 30 seconds will cause the tablet to go back into hibernation, also triggered by Tasker. 12v power will be pulled from the BCM of my vehicle which stays on after the vehicle has been shut off for X amount of time, so that the tablet can recharge if needed.

Dimmer - This will function the same as the backup camera. When the Arduino sees that the dash lights are on or off it will set the variable and trigger the DQVE process so that tasker can update the screen brightness.

Amplification - Because the headphone out only supports two channels (left/right) I will end up mirroring the front and rear channels. I'm not overly concerned about this because I don't watch movies or listen to many things with surround sound. The tablet does not have enough juice to drive the factory speakers so a 4x50 RMS amp will be installed behind the tablet where the factory headunit used to sit.

I think those are all the key points I can think of right now, everything else is basically what app to use for what. Once the stable build of Android 4.0 is released on XDA this project can officially take flight. I'll update this with my thoughts and ramblings as they develop.

I read you explication and I'm very interesting about this.
Do you have any Cornerstone apk? I would like try in my Huawei Ideos S7
Arduino Dueliminove how work for transmit the commands to the tablet?

regards JSoriano

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that describes how to re-map bluetooth hid profiles, should work with usb hid devices as well...waiting for my usb host mode cable to come in before I start testing on my Galaxy Note....might be an other simpler option?

Best of luck and regards,

Have you ever consider possibility to use CPJexr(CarPc Joycon Exr) to connect to Android tablet via usb host mode..

According webpage of developers it has only drivers for Windows, however it mentioned that after initial key assigments it can also work with Linux..
I wonder would it be possible to map controls to android commands as well...
anybody studied this matter before ?

Comment

I've lurked the forum for years and have recently been experimenting with installing my tablet into the dash of my car. I decided it was time to post what I have learned along the way and things I learn in the future along the way.

The tablet that I have decided to use on this build is a Dell Streak 7". I like things to look and function like OEM and I have run into several hurdles along the way, so I'll list what I have planned and what I learn on my build below here.

Front End - I will be using Android 4.0 with Cornerstone on this install. There is already a working beta for this device over on XDA forums, once the bugs are worked out I will upgrade my tablet. The final build of 4.0 for the DS7 is said to support Cornerstone which will be perfect for switching between media/nav/OBD in an incar installation. More info on Cornerstone can be found here: http://www.onskreen.com/cornerstone/

Internet Connectivity - OEM functionality means that the device should be connected to the internet without the use of my cell phone. My solution for this is to use a Cradlepoint MBR1000 (http://www.cradlepoint.com/products/mbr1000) router with a Verizon USB hotspot. This router will handle any authentication needed so it's a simple power on, power off, and can be hidden away in the car. As a bonus it gives me the opportunity to attach other devices to the local network in this project.

Steering Wheel Controls - This one was a must for me and the solution is very basic. I will be using an Arduino Dueliminove with ethernet shield to handle inputs from the steering wheel controls and will transmit that information to the tablet through something I call DQVE (Dock, HTTP Query, Set Variable, Execute Command). The concept here is very basic. The Arduino gets a command from the steering wheel controls and sets a variable, then it calls the DQVE process.

The DQVE process trips a USB pin so that the tablet thinks it has been docked

Tasker intercepts the dock and performs an HTTP query to the IP address of the Arduino

The HTTP query returns an XML file that is parsed and the variable is set

Tasker performs the associated command

I will map mute, vol+/vol-, and track+/ track- to the specified commands and mode will launch Vlingo for voice command.

Backup Camera - Having a router in the car will allow me to install IP cameras and I can use the DQVE process to trigger tasker to launch an IPCam viewer application when the reverse lights are on.

Power Management - The plan is for the tablet to always be powered on. It's default resting state will have all connections and display off. The DQVE process will tell the tablet to wake up once the Arduino boots with key on. Loss of WiFi signal from the router for more than 30 seconds will cause the tablet to go back into hibernation, also triggered by Tasker. 12v power will be pulled from the BCM of my vehicle which stays on after the vehicle has been shut off for X amount of time, so that the tablet can recharge if needed.

Dimmer - This will function the same as the backup camera. When the Arduino sees that the dash lights are on or off it will set the variable and trigger the DQVE process so that tasker can update the screen brightness.

Amplification - Because the headphone out only supports two channels (left/right) I will end up mirroring the front and rear channels. I'm not overly concerned about this because I don't watch movies or listen to many things with surround sound. The tablet does not have enough juice to drive the factory speakers so a 4x50 RMS amp will be installed behind the tablet where the factory headunit used to sit.

I think those are all the key points I can think of right now, everything else is basically what app to use for what. Once the stable build of Android 4.0 is released on XDA this project can officially take flight. I'll update this with my thoughts and ramblings as they develop.

I am looking to do something very similar. I want to use a Pandaboard and basically make my own tablet. AOSP supports the Pandaboard as well. The issue I am running into now is how to get my steering wheel controls to work with it. I have a Ford Escape with Sync so I will be able to keep sync as well. Can you detail more of your so called DQVE? That seems like a perfect solution. Another solution for me would be to have the Arduino turn on voltages and the pandaboard addon board I will be getting has 5 buttons I can map to various things.